European Journal of Scientific Research - EuroJournals

Blind SIMO GSM Channel Identification 833
⎡
⎢
⎢
Y(
l)
Y ⎢ l =
⎢
⎢
⎢
⎣ 0
•
Y(
l−1)
•
0
Y(
l)
0 ⎤
− Y
⎥
( 1)
⎥
• ⎥
⎥
• ⎥
− Y ⎥
( l−1)
⎦
(27)
With l = 3,…,q and:
⎡ yl
( M )
⎢
⎢
•
Y ⎢ ( l ) = •
⎢
⎢ •
⎢
⎣y
l ( N −1)
•
•
•
•
•
•
yl
( 0)
⎤
•
⎥
⎥
• ⎥
⎥
• ⎥
y ( N − M −1)
⎥
l ⎦
(28)
In the presence of noise, equation (26) can be naturally solved in the least- square (LS) [4]
sense according to:
ˆ
H H
= argminh
Y Y h
(29)
hCR q q
h = 1
5. Simultion Results
We now present simulation results of GSM blind identification. A GMSK pulse of four symbols was
generated and bandwidth BT=0.3. The bit rate is 27 kb/s.
Figure 3: Estimation of propagation channel.
s(t): transmitted signal BPSK
n(t): additive noise
h(t): combined filter [h(t)=h0(t)*hc(t)]
Figure 3 represents the estimated impulse response of the propagation channel for COST-207
[6]. Figure 4 represents the relative error estimation for training method and blind method.